* {
  box-sizing: border-box;
}

ul {
  list-style-type: none;
}

body {
  font-family: Verdana, sans-serif;
  background: #E8F0F3;
}

#calendar {
  width: 80%;
  margin: 0 auto;
  box-shadow: 0 2px 2px 0 rgba(0, 0, 0, 0.14), 0 3px 1px -2px rgba(0, 0, 0, 0.1), 0 1px 5px 0 rgba(0, 0, 0, 0.12);
}

.month {
  width: 100%;
  background: #00B8EC;
}

.month ul {
  margin: 0;
  padding: 0;
  display: flex;
  justify-content: space-between;
}

.year-month {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: space-around;
}

.year-month:hover {
  background: rgba(150, 2, 12, 0.1);
}

.choose-year {
  padding-left: 20px;
  padding-right: 20px;
}

.choose-month {
  text-align: center;
  font-size: 1.5rem;
}

.arrow {
  padding: 30px;
}

.arrow:hover {
  background: rgba(100, 2, 12, 0.1);
}

.month ul li {
  color: white;
  font-size: 20px;
  text-transform: uppercase;
  letter-spacing: 3px;
}

.weekdays {
  margin: 0;
  padding: 10px 0;
  background-color: #00B8EC;
  display: flex;
  flex-wrap: wrap;
  color: #FFFFFF;
  justify-content: space-around;
}

.weekdays li {
  display: inline-block;
  width: 13.6%;
  text-align: center;
}

.days {
  padding: 0;
  background: #FFFFFF;
  margin: 0;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-around;
}

.days li {
  list-style-type: none;
  display: inline-block;
  width: 14.2%;
  text-align: center;
  padding-bottom: 15px;
  padding-top: 15px;
  font-size: 1rem;
  color: #000;
}

.days li .active {
  padding: 6px 10px;
  border-radius: 50%;
  background: #00B8EC;
  color: #fff;
}

.days li .other-month {
  padding: 5px;
  color: gainsboro;
}

.days li:hover {
  background: #e1e1e1;
}